The demand for wireless communication of voice and data is constantly increasing. Some wireless communication devices can include a transceiver that implements a direct upconversion and downconversion system. Direct upconversion describes a system in which an information-carrying baseband signal is mixed directly with a high-frequency local oscillator (LO) carrier signal. The combined radio frequency (RF) signal is amplified and transmitted from the wireless communication device. Likewise, direct downconversion describes a system in which a received RF signal is downconverted by using an LO to remove the carrier signal from the received RF signal to obtain the information carrying baseband signal. In either case, the baseband signal can be split into both in-phase (I) and quadrature-phase (Q) components.
A single LO is often employed for both upconversion and downconversion in a transceiver to maintain simplicity of the design, such that cost and size can both be reduced. However, the implementation of a single LO can result in distortion that is based on an imbalance of the gain and/or phase of the I- and Q-components of the signal. This imbalance can often greatly increase the need for expensive filters. Such an imbalance can be corrected through manual calibration that is often implemented on a trial-and-error basis. However, it is difficult to ascertain where the distortion is being introduced into the system. In addition, temperature and semiconductor aging can also result in dynamic distortion of a transceiver, such that the manual calibration is insufficient to provide long term correction of imbalance of the I- and Q-components of the transmitted and received signals.